As an optical module in which MEMS technology is used, for example, there is an optical module including an electrostatic actuator and a Fabry-Perot interference filter. In the Fabry-Perot interference filter, a distance between a pair of mirrors is changed by the electrostatic actuator, and light having a wavelength according to the distance is transmitted. Therefore, to increase the wavelength resolution of the Fabry-Perot interference filter, it is necessary to stably move the mirror using the electrostatic actuator with high precision.
Therefore, technology for controlling the operation of the mirror by detecting a change in electrostatic capacitance of the electrostatic actuator has been proposed (for example, see Patent Literature 1). According to this technology, it is possible to appropriately operate a mirror regardless of the instability of an applied voltage, a change in an ambient temperature, and the like.